FolioLanternBeta
GENBGenerate Biomedicines, Inc. · Insider ownership research

Generate Biomedicines, Inc. insiders sold $16K in the past 12 months. How much of their stake is that?

Insiders sold $16K in the past 12 months.100% was sold under disclosed trading plans. The largest seller, Frances Arnold (Director), sold $16K.Share-of-stake figures for this company are being verified and will be added when that check is finished. Why

Updated Oct 13, 2026 from SEC filings · covers Oct 14, 2025 to Oct 13, 2026
5
buyers among officers and directors (8 trades), past 12 months
100%
of sales were under disclosed trading plans, past 12 months
1 of 15
officers and directors sold shares, past 12 months
Latest filing: Filed Sep 3 for a sale on Sep 1. Frances Arnold sold 1K shares ($16K) under a disclosed plan. Filing
SEC ownership filings: 34 filed in the 12 months to Oct 13, 2026; 34 on record since Feb 26, 2026 · See the evidence

What stands out

Five insiders bought shares: Noubar Afeyan (3.12M shares, $50.0M), Michael Nally (20K shares, $240K) and Jason Silvers (2K shares, $32K), plus 2 more. These are the first purchases by current officers or directors in the filings on record.Noubar Afeyan: purchase, Mar 2, 2026 · Michael Nally: purchase, Mar 4, 2026 · Jason Silvers: purchase, Mar 2, 2026

A share of stake is shown for 0 of the 1 officer or director who sold. 15 are left out

i
Left out: Noubar Afeyan, Michael Nally, Gevorg Grigoryan, Frances Arnold, Stephane Bancel, Marsha Fanucci, Aarif Khakoo, Rupert Vessey, Beth Grous, Laurie Lee, Jane Mendillo, Nancy Simonian, Paul Parker, Jason Silvers and Sean Martin (share of stake is being verified).
Disclosed company stock is not an insider's whole wealth.

Who sold, and how much of their stake

Officers and directors, past 12 months. Their share of stake is being verified and is not shown yet; amounts and trading plans are below.

Frances Arnold
Director
Not confirmed
Share of stake not shown: share of stake is being verified. Why
$16KDisclosed plan
Amounts, filings and trading plans for each seller

Selling by month

Officers and directors, Oct 2025 to Oct 2026. Each sale is counted once: under a disclosed plan, else to cover taxes, else no plan disclosed.

Disclosed planOne dollar scale for every month; the tallest bar is labeled
OctNovDecJanFebMarAprMayJunJulAugSep 2026: $16K under a disclosed plan$16KSepOct

Recent activity

Past 30 days, Sep 14, 2026 to Oct 13, 2026

No officer or director trades were reported for the past 30 days. The most recent before that:

Sep 1, 2026Frances Arnold sold 1K shares ($16K) under a disclosed trading plan.
WhoSharesPrice% of total stakeTotal stake afterTrade dateFiled
Frances Arnold
Director
1,000$16.00n/an/aSep 1, 2026Sep 3, 2026

Outside holders, reported separately

Noubar Afeyan reported no open-market sales in the past 12 months. Large shareholders and the funds or companies that board members represent are not part of management, so they are left out of the figures above.

Details

Common questions

Is the Generate Biomedicines, Inc. CEO selling stock?

No. Michael Nally reported no open-market sales in the past 12 months.

Why are Generate Biomedicines, Inc. insiders selling?

Filings rarely give a reason, and we don't guess at one. What they show is how the sales were made: 100% of sales by value ran under 10b5-1 trading plans disclosed in the filings. A trading plan schedules sales in advance.

Are any Generate Biomedicines, Inc. insiders buying?

Yes. 5 officers or directors reported 8 purchases in the past 12 months (Form 4 code P; rows the filings describe as reinvested dividends, plan purchases, private deals or moves into the person's own trust are not counted).

The evidence

Who sold1 officer or director: amount, % of holdings, trading plan
Who soldAmount% of holdingsTrading plan
Frances Arnold
Director
$16K
1K shares
Not confirmed
share of stake is being verified. Why
Disclosed plan

Board members representing outside shareholders, reported separately: Noubar Afeyan. Details

The full ownership picture0 of 15 officers and directors confirmed

Vested shares across all share classes, held directly and through trusts, LLCs and family members, as reported on SEC Forms 3, 4 and 5. Unvested awards and options are never counted as owned shares.

InsiderHeld Oct 13, 2025SoldHeld Oct 13, 2026Still held
Noubar Afeyan
!
Holdings and share of stake are being verified. Share-of-stake figures and holdings for this company are held back while they are verified. See the filing Sales and other transactions for Noubar Afeyan are complete.
Director
n/a0n/an/a
Vesting, gifts, unvested awards and holding lines for Noubar Afeyan

Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Noubar Afeyan are complete; balances and unit counts will be added when the check is finished.

0gifted (net of own trusts)

Stock options (not counted as shares):

Options heldStrike priceExpiresIntrinsic value (estimate)
32,916$7.25Feb 8, 2034$288K
32,916$9.15Feb 20, 2035$226K
29,561$16.00Feb 25, 2036$59
29,561$16.00Feb 25, 2036$59

Estimate: options held × ($16.00 − strike price), using the most recent insider trade price on Form 4 (Sep 1, 2026), not a market close.

Michael Nally
!
Holdings and share of stake are being verified. Share-of-stake figures and holdings for this company are held back while they are verified. Sales and other transactions for Michael Nally are complete.
Chief Executive Officer, Director
n/a0n/an/a
Vesting, gifts, unvested awards and holding lines for Michael Nally

Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Michael Nally are complete; balances and unit counts will be added when the check is finished.

0gifted (net of own trusts)

Stock options (not counted as shares):

Options heldStrike priceExpiresIntrinsic value (estimate)
2,210,829$0.34May 27, 2031$34.6M
631,665$0.34May 27, 2031$9.9M
315,832$0.34May 27, 2031$4.9M
572,745$7.19Dec 3, 2033$5.0M
526,662$7.25Feb 28, 2034$4.6M
658,327$9.15Feb 20, 2035$4.5M
844,595$16.00Feb 25, 2036$2K
844,595$16.00Feb 25, 2036$2K

Estimate: options held × ($16.00 − strike price), using the most recent insider trade price on Form 4 (Sep 1, 2026), not a market close.

Gevorg Grigoryan
!
Holdings and share of stake are being verified. Share-of-stake figures and holdings for this company are held back while they are verified. Sales and other transactions for Gevorg Grigoryan are complete.
Chief Technology Officer
n/a0n/an/a
Vesting, gifts, unvested awards and holding lines for Gevorg Grigoryan

Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Gevorg Grigoryan are complete; balances and unit counts will be added when the check is finished.

0gifted (net of own trusts)

Stock options (not counted as shares):

Options heldStrike priceExpiresIntrinsic value (estimate)
131,665$6.05Apr 18, 2032$1.3M
131,665$7.19Dec 3, 2033$1.2M
131,665$7.25Feb 8, 2034$1.2M
230,414$9.15Feb 20, 2035$1.6M
295,608$16.00Feb 25, 2036$591
196,368$16.00Feb 25, 2036$393

Estimate: options held × ($16.00 − strike price), using the most recent insider trade price on Form 4 (Sep 1, 2026), not a market close.

Frances Arnold
!
Holdings and share of stake are being verified. Share-of-stake figures and holdings for this company are held back while they are verified. Sales and other transactions for Frances Arnold are complete.
Director
n/a−1Kn/an/a
Vesting, gifts, unvested awards and holding lines for Frances Arnold

Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Frances Arnold are complete; balances and unit counts will be added when the check is finished.

0gifted (net of own trusts)

Stock options (not counted as shares):

Options heldStrike priceExpiresIntrinsic value (estimate)
32,916$6.10Mar 26, 2033$326K
32,916$7.25Feb 8, 2034$288K
32,916$9.15Feb 20, 2035$226K
29,561$16.00Feb 25, 2036$59

Estimate: options held × ($16.00 − strike price), using the most recent insider trade price on Form 4 (Sep 1, 2026), not a market close.

Stephane Bancel
!
Holdings and share of stake are being verified. Share-of-stake figures and holdings for this company are held back while they are verified. Sales and other transactions for Stephane Bancel are complete.
Director
n/a0n/an/a
Vesting, gifts, unvested awards and holding lines for Stephane Bancel

Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Stephane Bancel are complete; balances and unit counts will be added when the check is finished.

0gifted (net of own trusts)

Stock options (not counted as shares):

Options heldStrike priceExpiresIntrinsic value (estimate)
32,916$6.10Mar 26, 2033$326K
32,916$7.25Feb 8, 2034$288K
32,916$9.15Feb 20, 2035$226K
29,561$16.00Feb 25, 2036$59

Estimate: options held × ($16.00 − strike price), using the most recent insider trade price on Form 4 (Sep 1, 2026), not a market close.

Marsha Fanucci
!
Holdings and share of stake are being verified. Share-of-stake figures and holdings for this company are held back while they are verified. Sales and other transactions for Marsha Fanucci are complete.
Director
n/a0n/an/a
Vesting, gifts, unvested awards and holding lines for Marsha Fanucci

Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Marsha Fanucci are complete; balances and unit counts will be added when the check is finished.

0gifted (net of own trusts)

Stock options (not counted as shares):

Options heldStrike priceExpiresIntrinsic value (estimate)
131,665$9.15Mar 10, 2035$902K
29,561$16.00Feb 25, 2036$59

Estimate: options held × ($16.00 − strike price), using the most recent insider trade price on Form 4 (Sep 1, 2026), not a market close.

Aarif Khakoo
!
Holdings and share of stake are being verified. Share-of-stake figures and holdings for this company are held back while they are verified. Sales and other transactions for Aarif Khakoo are complete.
Chief Scientific Officer
n/a0n/an/a
Vesting, gifts, unvested awards and holding lines for Aarif Khakoo

Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Aarif Khakoo are complete; balances and unit counts will be added when the check is finished.

0gifted (net of own trusts)

Stock options (not counted as shares):

Options heldStrike priceExpiresIntrinsic value (estimate)
394,996$11.75Feb 2, 2036$1.7M

Estimate: options held × ($16.00 − strike price), using the most recent insider trade price on Form 4 (Sep 1, 2026), not a market close.

Rupert Vessey
!
Holdings and share of stake are being verified. Share-of-stake figures and holdings for this company are held back while they are verified. Sales and other transactions for Rupert Vessey are complete.
Director
n/a0n/an/a
Vesting, gifts, unvested awards and holding lines for Rupert Vessey

Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Rupert Vessey are complete; balances and unit counts will be added when the check is finished.

0gifted (net of own trusts)

Stock options (not counted as shares):

Options heldStrike priceExpiresIntrinsic value (estimate)
131,665$7.49Jul 3, 2034$1.1M
29,561$16.00Feb 25, 2036$59

Estimate: options held × ($16.00 − strike price), using the most recent insider trade price on Form 4 (Sep 1, 2026), not a market close.

Beth Grous
!
Holdings and share of stake are being verified. Share-of-stake figures and holdings for this company are held back while they are verified. Sales and other transactions for Beth Grous are complete.
Chief People Officer
n/a0n/an/a
Vesting, gifts, unvested awards and holding lines for Beth Grous

Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Beth Grous are complete; balances and unit counts will be added when the check is finished.

0gifted (net of own trusts)

Stock options (not counted as shares):

Options heldStrike priceExpiresIntrinsic value (estimate)
658,327$7.18Dec 3, 2033$5.8M
164,581$9.15Feb 20, 2035$1.1M
114,020$16.00Feb 25, 2036$228

Estimate: options held × ($16.00 − strike price), using the most recent insider trade price on Form 4 (Sep 1, 2026), not a market close.

Laurie Lee
!
Holdings and share of stake are being verified. Share-of-stake figures and holdings for this company are held back while they are verified. Sales and other transactions for Laurie Lee are complete.
Chief Medical Officer
n/a0n/an/a
Vesting, gifts, unvested awards and holding lines for Laurie Lee

Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Laurie Lee are complete; balances and unit counts will be added when the check is finished.

0gifted (net of own trusts)

Stock options (not counted as shares):

Options heldStrike priceExpiresIntrinsic value (estimate)
197,498$9.15Sep 15, 2035$1.4M
42,230$16.00Feb 25, 2036$84

Estimate: options held × ($16.00 − strike price), using the most recent insider trade price on Form 4 (Sep 1, 2026), not a market close.

Jane Mendillo
!
Holdings and share of stake are being verified. Share-of-stake figures and holdings for this company are held back while they are verified. Sales and other transactions for Jane Mendillo are complete.
Director
n/a0n/an/a
Vesting, gifts, unvested awards and holding lines for Jane Mendillo

Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Jane Mendillo are complete; balances and unit counts will be added when the check is finished.

0gifted (net of own trusts)

Stock options (not counted as shares):

Options heldStrike priceExpiresIntrinsic value (estimate)
131,665$6.05Dec 12, 2032$1.3M
32,916$9.15Feb 20, 2035$226K
29,561$16.00Feb 25, 2036$59

Estimate: options held × ($16.00 − strike price), using the most recent insider trade price on Form 4 (Sep 1, 2026), not a market close.

Nancy Simonian
!
Holdings and share of stake are being verified. Share-of-stake figures and holdings for this company are held back while they are verified. Sales and other transactions for Nancy Simonian are complete.
Director
n/a0n/an/a
Vesting, gifts, unvested awards and holding lines for Nancy Simonian

Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Nancy Simonian are complete; balances and unit counts will be added when the check is finished.

0gifted (net of own trusts)

Stock options (not counted as shares):

Options heldStrike priceExpiresIntrinsic value (estimate)
131,665$7.49Jul 3, 2034$1.1M
29,561$16.00Feb 25, 2036$59

Estimate: options held × ($16.00 − strike price), using the most recent insider trade price on Form 4 (Sep 1, 2026), not a market close.

Paul Parker
!
Holdings and share of stake are being verified. Share-of-stake figures and holdings for this company are held back while they are verified. Sales and other transactions for Paul Parker are complete.
Director
n/a0n/an/a
Vesting, gifts, unvested awards and holding lines for Paul Parker

Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Paul Parker are complete; balances and unit counts will be added when the check is finished.

0gifted (net of own trusts)

Stock options (not counted as shares):

Options heldStrike priceExpiresIntrinsic value (estimate)
131,665$9.15Jun 4, 2035$902K
29,561$16.00Feb 25, 2036$59

Estimate: options held × ($16.00 − strike price), using the most recent insider trade price on Form 4 (Sep 1, 2026), not a market close.

Jason Silvers
!
Holdings and share of stake are being verified. Share-of-stake figures and holdings for this company are held back while they are verified. See the filing Sales and other transactions for Jason Silvers are complete.
President & CFO
n/a0n/an/a
Vesting, gifts, unvested awards and holding lines for Jason Silvers

Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Jason Silvers are complete; balances and unit counts will be added when the check is finished.

0gifted (net of own trusts)

Stock options (not counted as shares):

Options heldStrike priceExpiresIntrinsic value (estimate)
874,259$6.05Sep 29, 2032$8.7M
263,331$7.25Feb 8, 2034$2.3M
213,956$9.15Feb 20, 2035$1.5M
295,608$16.00Feb 25, 2036$591
274,493$16.00Feb 25, 2036$549

Estimate: options held × ($16.00 − strike price), using the most recent insider trade price on Form 4 (Sep 1, 2026), not a market close.

Sean Martin
!
Holdings and share of stake are being verified. Share-of-stake figures and holdings for this company are held back while they are verified. Sales and other transactions for Sean Martin are complete.
Chief Legal Officer & GC
n/a0n/an/a
Vesting, gifts, unvested awards and holding lines for Sean Martin

Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Sean Martin are complete; balances and unit counts will be added when the check is finished.

0gifted (net of own trusts)

Stock options (not counted as shares):

Options heldStrike priceExpiresIntrinsic value (estimate)
874,259$6.05Aug 5, 2032$8.7M
131,665$7.25Feb 8, 2034$1.2M
164,581$9.15Feb 20, 2035$1.1M
190,034$16.00Feb 25, 2036$380

Estimate: options held × ($16.00 − strike price), using the most recent insider trade price on Form 4 (Sep 1, 2026), not a market close.

Holdings and share of stake for Generate Biomedicines, Inc. are being verified, so no balances, unit counts or percentages are shown. Sales, proceeds, plan and tax status, titles and dates come straight from individual filings.

What explains the selling$16K of sales by plan status, purpose, seller and month

Officer and director open-market sales: $16K across 1,000 shares. Plan status and stated purpose are separate questions, and a sale can have both.

By plan status

Purchases · 5 buyers (8 trades)

5 officers and directors bought shares in this period, in 8 trades(Form 4 code P, leaving out rows the filings describe as reinvested dividends, plan purchases, private deals or moves into the person's own trust). Across all their filings on record there are 8 purchase trades.

SellerShares soldProceedsUnder a disclosed planShare of totalSales dates
Frances Arnold
Director
1K$16K100%100%Sep 1, 2026 to Sep 1, 2026

Sales by month

MonthSale proceedsDisclosed planTo cover taxesNo plan disclosed
Oct 2025$0$0$0$0
Nov 2025$0$0$0$0
Dec 2025$0$0$0$0
Jan 2026$0$0$0$0
Feb 2026$0$0$0$0
Mar 2026$0$0$0$0
Apr 2026$0$0$0$0
May 2026$0$0$0$0
Jun 2026$0$0$0$0
Jul 2026$0$0$0$0
Aug 2026$0$0$0$0
Sep 2026$16K$16K$0$0
Oct 2026$0$0$0$0
Board members representing outside shareholders (1)Listed and sourced; not part of the management totals or the answer line

Directors whose reported holdings sit mostly in an investment fund or a corporate shareholder they represent, not in their own name, with beneficial ownership disclaimed except for their own financial interest. Listed and sourced here; not part of the management totals or the answer line. Shares a fund hands to its own investors are distributions, not sales.

Board memberHeld Oct 13, 2025SoldHeld Oct 13, 2026Still held
Noubar Afeyan
!
Holdings and share of stake are being verified. Share-of-stake figures and holdings for this company are held back while they are verified. See the filing Sales and other transactions for Noubar Afeyan are complete.
Director
n/a0n/an/a
Vesting, gifts, unvested awards and holding lines for Noubar Afeyan

Holdings and share of stake are being verified. Sales, proceeds, plan and tax status and dates for Noubar Afeyan are complete; balances and unit counts will be added when the check is finished.

0gifted (net of own trusts)
Known gaps and uncertainty15 officers and directors not confirmed

Holdings and share of stake are being verified. Balances, unit counts and every share-of-stake figure for Generate Biomedicines, Inc. are held back until that check is finished. Sales, proceeds, plan and tax status, titles and dates come straight from individual filings and are complete.

External context: we only cite outside events when a documented connection exists. None is shown for this period.

Sources and methodology34 filings on record, 34 filed in the 12-month period, and how we read them

All 34 Forms 3, 4 and 5 on record for Generate Biomedicines, Inc. (SEC CIK 2100782), filed from Feb 26, 2026 to Sep 3, 2026; 34 of them were filed in the 12 months this page covers, retrieved from SEC EDGAR on Oct 13, 2026. Prices are the ones reported in each filing, often weighted averages.

Holdings. Each holding line (a share class plus an owner, such as a trust or LLC) carries its last reported balance forward. Entities first reported during the period start at zero, so transfers between an insider's own trusts don't count as selling. Lines not reported for three years or more are listed separately and left out of totals.

Sales. A sale counts as under a 10b5-1 plan if its footnote cites one or the filing's Rule 10b5-1 box is checked, and as tax-related if its footnote cites tax obligations or sell-to-cover. Shares withheld by the company for taxes are listed separately. Sales with neither attribute are labeled "no plan disclosed".

Full methodology

Spotted something wrong on this page? Report an error. We check every report against the SEC filing and list what we fix in the corrections log.